Various 1,4-benzodiazepine compounds including nitrazepam, diazepam, medazepam, estazolam, and triazolam have been practically used as hypnotics, minor tranquilizers or psychotropic drugs. Recently, the mental disorders show a tendency to rapidly increase together with growth of the complexities in human society. As a result of intensive researches for central nervous system drugs which are more effective and broadly applicable to mental disorders, the present inventors have found that 4,1-benzoxazepines and 4,1-benzothiazepines have excellent central nervous system actions. This invention is based on this finding. The compounds having 1,4-benzodiazepine structure are well-known, and some compounds having 4,1-benzoxazepine or 4,1-benzothiazepine structure are described in German Patent No. 1,545,639, U.S. Pat. No. 3,346,638, Farmaco. Ed. Sci., 18, 815 (1963) and Ann. Chem., 1978, 1241. But the compounds of this invention shown hereinafter are novel.